Flour sifter



March 16, 1937. J. 5. BOWMAN FLOUR S IF'I'ER Filed Oct. 9, 1934 2Sheets-Sheet 1 INVENTOR Jfap'qoh $.Bowman.

- ATTORNEY.

\ Patented Mar. 1 6, 1937 PATENT OFFICE FLOUR SIFTER Joseph S. Bowman,El Paso, Tex., assignor to Westinghouse Electric & ManufacturingCompany, East Pittsburgh, Pa., a corporation of Pennsylvania ApplicationOctober 9, 1934, Serial No. 747,507

8 Claims. (Cl. 209-251) My invention relates to kitchen appliances andparticularly to motor-driven flour sifters.

An object of my invention is to provide a simple and efficient floursifter assembly to be associated with a motor-driven kitchen mixer orheater.

It is well known that better food products, particularly cakes, can beobtained if the flour and other dry ingredients mixed therewith have 10been sifted a plurality of times, and it is an object of my invention to,provide a device which will sift flour or-other dry ingredients aplurality of times.

Another object of my invention is to provide a flour sifter in which theposition of the material container is reversed repeatedly and in whichthe sifting element is reciprocated or actuated in a continuous manner.

Other objects of my invention will either be pointed out specificallyhereinafter, or will be apparent from the description of one form of thedevice embodying my invention.

In practicing my invention I provide a casing containing aspeed-reducing and driving mechanism readily mountable on a motorassembly constituting part of a kitchen food mixer and a materialcontainer removably and. rotatably mount- Fig. 2 is a view taken on theline II---II of Fig. 1 showing another view of the speed reducing anddriving mechanism, and,

Fig. 3 is an enlarged view showing the sifting element in the materialcontainer.

Referring to Figs. 1 and 2 of the drawings, I have there illustratedgenerally only a motor driven kitchen mixer or beater H comprising abase 1 3, a standard [5 thereon, upon which standard there is mounted amotor assembly I! having a handle I9 thereon so that if desired themotor assembly may be removed from the standard and used independentlythereof. Means for energizing the motor in the assembly H is shown inthe form of short'leads 2|, it being understood, of course, that theseindicate a twin conductor supply circuit energizablein the usual manner.

The motor assembly I! has depending therefrom a pair of beater rods orshafts 23 spaced apart a short distance and having beater elements (notshown) secured to the lower ends of the shafts 23. The shafts are drivenby means of a motor shaft 25 having worm threads on a part thereof,which threads mesh with two worm gears 21 on the upper ends of theshafts 23 or upon suitable tubular driving shafts into which extend theupper ends of shafts 23 in a manner well known in the art.- I haveillustrated a removable bowl 29 mounted upon a rotatable base 3|which-is supported from the fixed base I3 of the kitchen mixer. Thedetails thus far describedv constitute no part of my invention but havebeen shown in order to illustrate the cooperation between the deviceparticularly embodying my invention and a motor driven food mixer forop-.' erating the same.

One of the shafts 23 has associated therewith an upwardly extending stubshaft 33 having a laterally extending slot 35 in its upper end adaptindetail.

The device embodying my invention includes a mechanism-containing casing31 having removably and rotatively associated therewith a sifter.assembly 39. The latter includes a central casing portion H (seeparticularly Fig. 3) which may be of substantially circular contourlaterally thereof and which may bemade of sheet metal having a tubularextension 43 secured thereto, at one side thereof. A substantially fixedsieve 45 is located within the casing portion 4| in fixed positionrelatively thereto as by being soldered or welded to the inner wall ofcasing M, as is shown at 41.

A reciprocally movable sifter element 49 includes an upper and a lowerscreen of wire mesh, each being held in a substantially annular frame5|, which frame may be of substantially fiat channel shape in radialsection. An upper guide 53 and a lower guide 55, each of annular shapeand made of an angle bar member, are operatively associated with thesifter element 49 to hold the same in proper operative position withinthe casing portion 4i and to permit substantially continuous reciprocalmovements thereof. The material container includes also a pair ofclosure or end members 51 and 59 which may be of substantially the samesize and shape and which are removably associated with the casingportion 4|, being secured thereto as by means of pins 6! entering abayonet type slot in the respective closures 51 and 59, to cooperatewith the portion 4| to provide a double chamber or doubleended materialcontainer.

The complete material container assembly is rotatably mounted in anopening 53 in the front wall of casing 31 substantially as shown in Fig.1 of the drawings, and is held in such position by a lug 54 on amanually actuable latch 65, which lug enters a peripheral recess 61 inmember 43. The annular members 5! have secured thereto, as

by welding or in any other approved manner, a

shaft lug 69, theouter end of which is in turn secured to a short shaftII which extends out wardly through the closed outer end of member 43.Shaft H is provided with an annular recess at that portion thereoflocated within the hollow tubular member 43 and a stop plate I3, whichmay be of substantially U-shape fits into the recess to limit themovement of shaft H and of the screens 49 in one direction. These partsare yieldingly urged in one direction by a helical spring [5 surroundingthe shaft H and located within the tubular member 43, one end of whichengages plate 13 and the other end of which engages a,

plate 11 (see Fig. 3) which abuts against one part of easing portion 4|.The two screens 49 are therefore yieldingly urged in one direction, tothe right as seen in Figs. 1 and 3 of the drawings, from which thesifter element may be moved in the other direction by means now to bedescribed.

Casing 31 has located therein a shaft 19 which has at its lower end atongue 3| to interfit with the slot 35 hereinbefore described in shaft33. The upper end of shaft 19 is provided with a pinion 83 and fits intothe bearing lug 35 which may be integral with a part of casing 31. Asecond shaft 81, having a gear 89 secured thereon at its upper end whichmeshes with pinion 83, is sup ported within the casing 31 as by abearing lug 9| at its upper end and a bearing bracket 93 supporting theshaft at its lower end. Shaft 31 has mounted thereon a cam 95, thedimensions of which are such that the outer end of sifter shaft II willjust engage the same in one position of cam 95 while shaft 'II and theelements associated therewith will be moved toward the left against thespring 15 when cam 95 has been turned through substantially from theposition shown inFig. 1 of the drawings. Rotation of shaft 81 thereforeresults in reciprocal movement of the sifter element in the materialcontainer, cam 95 moving the sifter element to the left from whichposition it is returned by the action of sprin Means for reversing theposition of the material container 39 includes a pinion 91 fixedlymounted on shaft H and engaged by a rack ha 99 movable verticallyupwardly and downwardly in suitable bearing brackets II and I93, shownin Figs. 2 and 3 of the drawings. The lower end of rack bar 99 isprovided with a laterally pro- J'ecting lug I05, which lug is adapted tofit into a cam groove Ill! formed in the cam disc I99, which cam disc ismounted on a shaft II I having a horizontal axis. Shaft III has securedthereon a worm wheel I I3 which is adapted to be engaged by a wormthreaded portion I IS on shaft 19.

While I have illustrated and described specific details of a speedreducing and driving mechanism for the material container, I desire itto be understood that I do not wish to be limited to the specificdetails shown, but that other forms of device effective for the samepurpose may be utilized, the details now shown and described be ingthose now preferred by me.

As shown more particularly in Fig. 1 of the drawings, the casing 31 mayinclude two portions which may be bolted together, one of the-portionsof casing 31 being provided with apertured lugs 1 through which suitableclamping bolts (not shown) may extend. The casing 31 and the partssupported thereby may be removably mounted on. the forward end of motorassembly I! by one or more clamping screws H9. While I have shown twosuch clamping screws H9, other equivalent clamping means may beprovided.

If it be assumed that casing 31 has been mounted in proper operativeposition on motor H, the operator can remove, say the lower coverportion 51, of the material container and put therein the desired amountof flour with or without other dry ingredients. The cover member is thenplaced in its proper operative position relatively to its casing member4| and the motor may then be energized. This will operate stub shaft 33which in turn will cause rotative movement of shaft 19 which rotativemovement is transmitted to the cam 95 on shaft 81, causing the cam torotate and to move shaft II and the sifter elements connected therewithto the left, the spring 15 causing these members to return to the right.This motion is substantially continuous, the number of suchreciprocatory movements being determined by the speed of shafts 33 andI9 and the ratio of transmission impressed by pinion 83 and gear 89.

At the same time, cam disc I09 is caused to rotate by the action of thescrew threaded portion 5 of shaft 19 on Worm wheel H3, and it is to benoted that the cam groove I0! is such that rack bar 99 is held in, sayits upper position, as shown in Figs. 1 and 2 of the drawings for almostone-half complete turn of disc I99 after which rack bar 99 is moveddownwardly and is then held in its lower position for almost one-halfcomplete turn of disc I09. This movement of rack bar 99 meshing withpinion 91 causes a turning movement of the material container 39 from aposition where cover member 59 is uppermost to .the inverted positionwhere cover member 51 is uppermost. Since the reciprocatory movement ofsifter elements 49 continues irrespective of the position of thematerial container, it is obvious that the dry material located in theuppermost portion of the material container will be sifted downwardlyinto the lower portion, and the relation between the various parts ofthe driving and actuating mechanism is such that all of the fiour orother material to' besifted will be caused to move through the sifterfrom the upper into the lower part of the container before the containeris reversed as to its position.

The device embodying my invention thus provides a relatively simple andcompact assembly for simultaneously actuating a sifter element in thematerial container and for intermittently reversing the position of saidmaterial container in sequence.

. While I have illustrated and described a specific embodiment of adevice embodying my invention, namely that embodiment now preferred byme, I do not desire to be limited thereto,

since obvious modifications may be made therein and the scope of theinvention is to be limited only by the prior art or by the appendedclaims.

I claim as In," invention: 1. In combination with an electric motorhaving a driving shaft, a sifter assembly including a container formaterial to be sifted, an agitator in the container and means actuatedby the driving shaft to continuouslyreciprocate the agitator and tointermittently invert the con-- tainer.

2. In combination with an electric motor having a driving shaft, asitter assembly including a container for holding material to be sifted,a sieve and a movable agitator in the container and means actuated bythe driving shaft to cause continuous movement of the agitator andintermittent inverting tainer.

-3. In combination with an electric motor havmovement of the conshaft tocause intermittent yiversion of the container, a sieve-and a movableagitator in the container, resilient means to bias the agitator to oneposition in its travel, and means actuated by the driving shaft to movethe agitator against the resilient biasing means irrespective of suchinversion of the container. a 4. In combination with an electric motorhaving a driving shaft, a sitter operatively associated therewith andincluding a horizontally pivotally mounted material container and meansactuted by the driving shaft and including a rotatable element having acam slot therein for 30 intermittently sequentially turning thecontainer around its horizontal pivotal axis through substantially 180.

5. m sitter assembly including a casing, a power shaft in the casing, acontainer for ma- 35 terial to be sifted, an agitator in the container.

and driving mechanism including said .power shaft effective toreciprocate the agitator and to intermittently invert the container.

6. In combination with an electric motor having a shaft, a sitterassembly operatively associated with the motor and comprising a casing,a material container removably rotatively mounted in the casing, asitter element in the container and reciprocally movable therein, aspring holding the sitter element in one position, a cam in the casingoperativeiy engaging the sifter element to move it to another positionand means in the casing including a cam disc to intermittently reversethe position of the material container.

7. In combination with an electric motor having a driving-shaft, asitter assembly operatively associated with and mounted on "the motorand comprising a casing, a material container rotatively and removablymounted in the casing, a reciprocally movable 'sifter element in thematerial container, a spring in the material container yieldingly urgingthe sifter element in one direction, a cam in the casing actuated by thedriving shaft, operatively engaging the sifter element to move itagainst the pressure of the spring, a pinion on the material container,a rack bar in the casing engaging the pinion and means .including a camdisc for actuating the rack bar.

' 8. In combination with an electric motor having a driving shaft, asitter assembly mounted on the motor and including a container forholding material to be sifted, a sieve and a movable agitator in thecontainer, a spring for biasing the agitator to one extreme position,cam

'means actuated by said driving shaft to recurrentiy move the agitatoragainst said spring, and cam means actuated by the driving shaft tocause inversion of said container after a predetermined number ofmovements of said agitator.

JOSEPH S. BOWMAN.

